Richard Huxton <dev@archonet.com> writes:
> Gauthier, Dave wrote:
>>> Trying (and failing) to attach to my DBs. Getting...
>>> database "foo_standby" has disappeared form pg_database
>>> DETAIL: Database OID 2323523 now seems to belong to "foo"
> Hmm - if a shutdown + restart fixed it, I'm wondering if it wasn't just
> a long-lived connection remembering where 2323523 used to point to.
No, it's the "flat file" copy of pg_database that's supplying that
number, and the reason the restart fixed it is that the flat file
is forcibly rebuilt during a restart. What's not quite clear is
why the flat file was wrong.
We've seen this type of failure reported from the field before,
and as far as I recall the triggering condition was transaction ID
wraparound due to lack of vacuuming ... but haven't consumed enough
caffeine this morning to remember details.
regards, tom lane